Vehicle drawbar lock



Aug. 9, 1949.

H. C. RIEMANN ET AL VEHICLE DRAW BAR LOCK Fi led June 7, 1946 109.5 yMix/2m Patented Aug. 9, 1949 R. Thorp, West Allis, Wls., assignors" toThe Fulton Company, West Allis; Wis., a corpora;

tion of Wisconsin Application June 7, 1946, Serial No. 675,050] 1 Ourinvention relates in general to improvements in devices forconnectingone vehicle to another, and relates more specifically toimprovements'in the construction and operation of mechanism for lookinga vehicle draw bar in several positions. 7

The rincipal object of the present invention is to provide simple andefilcient means for looking a vehicle draw bar in either active orinactive position.

Many different types of draw-bars for connecting, a trailer to a draftvehicle, have heretofore been proposed and used commercially; and asshown in cop'ending application Serial No. 568,576, filed December 18,1944, now Patent 2,408,531, issued October 1, 1946, it has also beenproposed to utilize a flat elongated draw bar pivotally suspended from atransverse bracket carried by an automobile frame near the rear bumper;to connect the automobile to a trailer through aninterveningballcoupling. In such a trailer hitch assemblage, it is preferable tohave the elongated draw bar carrier bracket. concealed by the rearbumper and by. the vehicle body, and to so mount thedraw bar that it mayeither be projected rearwardly beyond the adjacent bumper when in activeposition,. or swung forwardly and concealed by the bumper. and bodytogether with its suspension bracket when in inactive position. In orderto eliminate looseness in the draw bar mounting and resultant rattling,itisdesirable to positively lock the draw bar in both active andinactive positions, andlooking a draw bar or the like in severaldifferent positions, as when the draw bar is active or;

inactive.

'Another specific object of this invention is to" rovide aconvenientlymanipulable:locking assemblage for efiectivelypreventing'looseness or rattling of a draw bar when disposed ineither10' Claims. (Cl. 28033.44)"' sold at moderate cost, and which is.adapted for diverse uses.

These and otherspecifi-c objects and advantages; of the invention willvbe apparent from the fol; lowing detailed description.

' A clear conception of'the' features constituting the presentimprovement; and of the-manner in which a typical embodiment of'theinvention maybe constructed and utilized, may be h'ad'by referring tothe drawing accompanying and forming a part ofthis'specification-wherein like refer ence characters designate the sameor similar parts in the various views.

Fig. 1 is a side elevation of a typical-vehicle draw bar and suspensionbracket, showing, the draw bar in active position in solid lines, and"in inactive position in dot-and-dash lines, and. also depicting asection through the suspension bracket? Fig; 2 is a bottom view of thedraw bar assemblageshown' in Fig. 1, illustrating only a fragment' ofthe elongated transverse suspension bracket; and I Fig; 3'is an enlargedfragmentary view of. the improved draw bar lock, showing the manipulateing handle in section.

Whilethe invention has been illustrated and described herein as beingespecially advantageousl applicable to a flat elongated vehicle drawbarof the type specifically shown in the aboveidentified, copendingapplication, it is not inverted U-shaped bracket 6 adapted to be firmlyattachedlin any suitable manner to the rear portion of a draft'vehicle,and having laterallyspaced sideplat'es 1, 1' secured to and extendingrearwardly from the medial part thereof; apivot pin 8 firmly, unitingthe upper rear portions of the side plates 1, 7; a stop rod 9 likewisefirmly interconnecting the lower rear portions of theside plates 1, 1';anelongatedflat and rather irregular draw bar I'll having an integralloop I I at one end swingably" embracing the pivot pin 8 while itsopposite swinging end is provided with an opening I2 for attachment ofa. trailer thereto;

anda wedge lock c'arried'bythe side plate I and having two independentwedges I4, I5 cooperable withthe draw bar In and with long and shortslots [5, l? in the two side. plates 1, i tolinterchangeably lock th barlnin either active position as shown in solid lines, or inactiveposition as shown in dot-and-dash lines.

When applied to standard automobiles, the transverse bracket 6 of thehitch, is firmly secured to the vehicle frame in front of the rearbumper, and both the bracket 6 and its side plates 1, l are normallyconcealed from view by the rear bumper bar and the rear splash plate ofthe car body, so that access to the hitch may be gained only frombeneath. The bracket 6 may be formed of channel bar stock or from metalplate bent into U-shape with the aid of a punch, and the side plates I,1 may be formed of sturdy metal plate welded to the channel bar. Thepivot pin 8 is normally disposed beneath the rear splash plate andforwardly of and above the lower edge of the bumper bar, thus making itnecessary to distort the medial portion of the draw bar II] as shown, inorder that this bar may clear the bumper when in active position asshown in solid lines. The draw bar I is preferably formed of heavy metalstock, and has a medial socket portion I9 adapted to be firmly clampedagainst the stop rod 9 by the wedge I4 when the draw bar is in use, andis also provided with a flat medial portion adapted to be clampedagainst the top of the bracket 6 by the other wedge I5 when the bar I 0is not in use.

The two wedges I I4, I5 of the improved draw bar lock, and which coactwith the slots I6, I! of the side plates I, I when in looking position,are also formed of heavy metal, and are secured at their outer widerends to a pair of connecting straps H, 22, by means of rivets 23. Themedial portions of the straps 2I, 22 form a bore 24, within which theinner reduced end 25 of a wedge manipulating handle 26 is journalled forrotation, and this handle 26 is provided with a central bore 21 and withintern-a1 screw threads 28 within the reduced and 25, the latterextending inwardly beyond the bore 21 and providing a stop abutment forthe handle 26. The handle 26 is also provided with a flange 29 engagingthe straps 2|. 22, and is mounted upon a shaft 30 one end of which isrigidly secured to the side plate I by a weld 3| and is also providedwith external screw threads 32 normally coacting with the screw threads28. The fixed shaft 3|] extends through the handle bore 27 and has astop washer 33 secured to its outer end, this washer 33 being adapted toengage the abutment formed by the internal screw threads 28 of thehandle 26 when these threads have been disengaged from the shaft threads32 for withdrawal of the wedges I4, I5, see Fig. 3.

With the foregoing assemblage of elements, the wedges I4, I5 mayobviously be simultaneously withdrawn from the slots I1 and from thespace between the side plates 1, l, by merely unscrewlng the threads 28from the threads 32 and by thereafter sliding the handle 26 along itssupporting shaft 36, until the abutment formed by the internal threads28 engages the stop washer 33, whereupon the handle will be stopped andthe narrower ends or tips of the wedges I4, I5 will lie within the widerslots I6 of the side plate I and the draw bar ID will be free to beswung be tween the plates 1, 1. However, when the screw threads 28, 32are brought into engagement with each other by sliding, the handle 26 inthe opposite direction and by rotating it about the shaft 36, then thewedges I4, I5 will be driven into the slots I6, I "I and against thedraw bar I0 as indicated in Fig. 1. so as to firmly lock the draw bar ineither active or inactive position; and in order to retain the parts inlocked position, the handle 26 is provided with a serrated plate 36welded thereto and provided with detents 31 adapted to be engaged by alatch ball 38 which is confined within a socket 39 formed in the strap2I and is forced outwardly by a compression spring 40. When the wedgesI4, I5 have been driven home, the ball 38 will engage the nearest detentand will frictionally but firmly hold the handle 26 in position, thuspreventing undesirable loosening of the wedges I4, I5, see Figs. 1 and2.

During normal use of the improved draw bar and locking assemblage, afterthe various elements have been properly constructed and assembled, thebracket 6 may be secured to the automobile frame so that it togetherWith the side plates 1, l and the pin 6 and stop rod 9 will be concealedby the vehicle rear splash plate and bumper, in a well known manner. Thedraw bar I6 may thereafter be positioned and locked, either in activeposition extending rearwardly of and beneath the rear bumper as shown insolid lines in Figs. 1 and 2, or in inactive inverted and concealedposition as shown in dot-and-dash lines, and this alternate positioningof the bar It] may be readily and quickly effected by merely unscrewingthe threads 28 of the handle 26 from the threads 32 of the fixed shaft36 and by thereafter sliding the handle 26 outwardly until the abutmentthreads 28 engage the stop washer 33. This outward sliding motion of thehandle 26 will cause the flange 29,at' the inner end thereof to engagethe straps 2I, 22 and to withdraw the wedges I4, I5 from within thespace between the side plates I, I, thus releasing the draw bar Ill andpermitting it to be swung freely about its pivot pin 8 and within thisspace to either active or inactive position. When the draw bar has beentemporarilypositioned with its socket portion I9 against the stop pin 9and the handle 26 and wedges I 4, I5 are moved inwardly, and the handleis subsequently screwed onto the shaft threads 32, the draw bar I6 willbe firmly clamped against the stop rod 9 and locked in active positionby the latch ball 38; whereas, if the draw bar I6 is temporarilypositioned with its medial portion 26 in contact with the top of thebracket 6 and the handle 26 is likewise applied to the shaft threads 32,the bar II) will be firmly clamped against the bracket 6 and locked ininactive position by the latch ball 38.

From the foregoing detailed description it will be apparent that thepresent invention provides an improved vehicle draw bar lock, whichbesides being simple and compact'in construction is convenientlymanipulable to firmly maintain the draw bar in several differentpositions of adjustment. The improved locking assemblage may obviouslybe applied to various types of swingable draw bars and the wedges I4, I5may be positioned in any desired radial planes relative to the axis ofthe handle 26 and shaft 36, thus making the improvement flexible in itsadaptations. The clamping wedges I4, I5 cooperate with the slots I6, !1and with the stop rod 9 and bracket 6 to firmly clamp the draw bar ID inthe several different positions and the ball latch 38 effectively locksthe parts in clamping position and positively prevents looseness andresultant rattling. The improvement has proven highly successful andsatisfactory in actual use, and may be manufactured and applied to thetrailer hitches at moderate cost.

It should be understood that it is not desired to limit this inventionto the exact details of construction or to the precise mod of use,herein shown and described, for various modifications within the scopeof the appended claims may occur to persons skilled in the art.

We claim:

1. A draw bar lock comprising, a supporting bracket having side platesprovided with slots, a draw bar pivotally suspended from said bracketside plates, a plurality of wedges coo-perab-le with said slots and withsaid draw bar to clamp the latter in either active or inactive position,a single handle for manipulating all of said wedges, and a latchcoacting with said handle to maintain the same in the several positionsof adjustment.

2. A draw bar lock comprising, a supporting bracket having laterallyspaced side plates, a draw bar pivotally suspended fro-m said bracketand being swingable in the space between said plates from active toinactive position and vice versa, a pair of wedges cooperable with saidside plates and with said draw bar to clamp the latter in either of saidpositions, and a handle cooperating with said draw bar and with saidbracket to move said wedges into and out of said space and to clamp saiddraw bar in either of said positions.

3. A draw bar lock comprising, a supporting bracket having laterallyspaced side plates, a draw bar pivotally suspended from said bracket andbeing swingable in the space between said plates from active to inactiveposition and vice versa, a pair of wedges cooperable with said sideplates and with said draw bar to clamp the latter in either of saidpositions, a handle cooperating with said draw bar and with said bracketto move said wedges into and out of said space and to clamp said drawbar in either of said positions, and a latch coacting with said handleto maintain the same in several positions of adjustment.

4. A draw bar lock comprising, a supporting bracket having laterallyspaced side plates one of which is provided with a threaded shaftextending outwardly therefrom, and both of which are provided withalined slots, a draw bar swingably suspended between said plates, a pairof wedges coacting with said slots and being cooperable with said slotsto clamp said draw bar in either active or inactive position, and meanscoacting with the screw threads of said shaft for actuating said wedges.

5. A draw bar lock comprising, a supporting bracket having laterallyspaced side plates one of which is provided with a threaded shaftextending outwardly therefrom, and both of which are provided withalined slots, a draw bar swingably suspended between said plates, a pairof wedges coacting with said slots and being cooperable with said slotsto clamp said draw bar in either active or inactive position, and ahandle having screw threads cooperable with said shaft threads and beingmovable along the shaft to move said wedges into and out of said slots.

6. A draw bar lock comprising, a supporting bracket having laterallyspaced side plates one of which is provided with a threaded shaftextending outwardly therefrom, and both of which are provided withalined slots, a draw bar swingably suspended between said plates, a pairof Wedges coacting with said slots and being cooperable with said slotsto clamp said draw bar in either active or inactive position, a handlehaving screw threads cooperable with said shaft threads and beingmovable along the shaft to move said wedges into and out of said slots,and a latch cooperable with said handle to maintain the, saline invarious positions of adjustment.

7. A draw bar lock comprising, a supporting bracket having a side plateand a shaft 'projecting from one side of the plate, said plate havingslots therein radiating from said shaft, a draw bar pivotally suspendedfrom said plate to swing along the opposite side of the latter, a pairof wedges coacting with said slots and being cooperable with said drawbar to clamp the same in either active or inactive position, and ahandle having screw threads cooperable with the threads of said shaft todrive said wedges into clamping position.

8. A draw bar lock comprising, a supporting bracket having a side plateand a shaft projecting from one side of the plate, said plate havingslots therein radiating from said shaft, a draw bar pivotally suspendedfrom said plate to swing along the opposite side of the latter, a pairof wedges coacting with said slots and being co'operable with said drawbar to clamp the same in either active or inactive position, a handlehaving screw threads coo-perable with the threads of said shaft to drivesaid wedges into clamping position, and a latch carried by said wedgesand coacting with said handle to maintain the latter in variouspositions.

9. A draw bar lock comprising, a supporting bracket having a side plateand a shaft projecting from one side of the plate, said plate havingslots therein radiating from said shaft, a draw bar pivotally suspendedfrom said plate to swing along the opposite side of the latter, a pairof wedges coacting with said slots and being cooperable with said drawbar to clamp the same in either active or inactive position, a handlehaving screw threads cooperable with the threads of said shaft to drivesaid wedges into clamping position, and a stop on said shaft cooperablewith the screw threads of said handle to limit the movement of thehandle away from said plate.

10. A draw bar lock comprising, a bracket having spaced side platesprovided with alined slots, a draw bar swingably suspended from saidbracket side plates, wedge means slidably cooperable with said slots andwith said draw bar to clamp the latter in either active or inactiveposition, means for shifting said wedge means within said slots back andforth across the space between said side plates, and latch meanscoacting with said shifting means to maintain the draw bar in either ofsaid positions.

HOWARD C. RIEMANN. JOEL R. THORP.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 2,408,531 Riemann et al Oct. 1,1946

